US-based nuclear power and nuclear fuel recycling company Oklo is engaging with the US Nuclear Regulatory Commission (NRC) in a Pre-Application Readiness Assessment for its combined licence application (COLA) for its Aurora Powerhouse at the Idaho National Laboratory (INL). The assessment allows NRC staff to review and familiarise themselves with Oklo’s licensing materials ahead of the full application review.
The assessment is designed to specifically address the content of the first phase of Oklo’s COLA submission, which will include information on the siting and environmental portions of the application. By pre-emptively addressing NRC’s concerns and offering an opportunity to refine submitted information, the readiness assessment helps to streamline the formal review process.
Oklo is developing the Aurora microreactor, which uses heat pipes to transport heat from the reactor core to a supercritical carbon dioxide power conversion system to generate electricity. It will use high-assay low-enriched uranium (HALEU) fuel. Oklo says the reactor builds on the Experimental Breeder Reactor-II (EBR-II) and space reactor legacy. Oklo initially marketed a 1.5 MWe microreactor version of the Aurora but has now expanded its capacity offerings from 15 MWe to 100 MWe. Oklo received a site use permit from the US Department of Energy (DOE) in 2019 to build and operate a prototype reactor at INL and is working towards site characterisation for the first-of-a-kind plant.
Oklo has been engaged with the NRC since 2016, working to establish a clear regulatory pathway for its nuclear technology. The company has completed extensive pre-application engagement, including securing an approved quality assurance programme description and advancing key licensing areas such as safety analysis, operational programmes, environmental considerations, and component classification.
Based on the US 2024 ADVANCE Act, NRC is working to modernise the regulatory landscape for advanced nuclear. A key component of this is a significant reduction in licensing fees, making regulatory processes more accessible and cost effective for advanced reactor developers. NRC has proposed cutting the hourly rate for advanced reactor applicants by nearly 55%, with this change set to take effect on 1 October 2025.
“We continue making progress towards obtaining commercial licences for next-generation nuclear technologies,” said Oklo co-founder and CEO Jacob DeWitte. Oklo plans to submit a formal COLA later this year, with plans for follow on applications to fulfil its order pipeline of more than 14 GWe.
Earlier in March, following finalisation of a Memorandum of Agreement (MOA) with DOE, Oklo has entered into an Interface Agreement (IAG) with INL. This aims to ensure strict adherence to environmental regulations throughout the site investigation process and reinforces Oklo’s commitment to environmental stewardship throughout the project.
As part of the MOA and the IAG, Oklo worked closely with INL and DOE to prepare for site characterisation fieldwork. Preparations included comprehensive cultural and biological surveys conducted in partnership with local Shoshone Bannock Tribes. “These agreements and reviews mark progress towards constructing our first advanced fission powerhouse. We are focused on ensuring that our development processes are both efficient and sustainable,” said DeWitte.
In October 2024, DOE approved the Conceptual Safety Design Report for Oklo’s Aurora Fuel Fabrication Facility, marking progress toward deploying the fuel facility at INL in 2027. The facility will fabricate fuel for Oklo’s first commercial powerhouse, whose liquid metal-cooled, metal-fuelled fast reactor technology requires HALEU. Oklo plans to source five tonnes of HALEU from the former EBR-II reactor. As part of the next phases, Oklo is preparing its Preliminary Documented Safety Analysis (PDSA), with submission to DOE targeted for mid-2025, followed by the Documented Safety Analysis, a key regulatory requirement before operational licensing.
While the Aurora Fuel Fabrication project is still under development, Oklo has already begun regulatory engagement as part of a broader long-term effort to commercialize fuel recycling. Oklo is planning a commercial fresh uranium fuel fabrication facility to support its broader deployment goals. Separately, it is also developing fuel recycling, seeking to convert used fuel from light water reactors (in the form of ceramic oxide) to usable metallic HALEU fuel.
